Apparatus and method for inputting character using touch screen in portable terminal

ABSTRACT

A method of inputting characters in a portable terminal is provided. The method includes displaying a plurality of characters on a keyboard, detecting a touch on the keyboard, displaying one character corresponding to a key corresponding to the touch on the keyboard as enlarged relative to other characters upon detecting the touch, displaying the character, which is displayed enlarged when detecting a release of the touch, in a character input area upon detecting a release of the touch on the keyboard, and displaying a plurality of recommended words in a vicinity of the keyboard based on characters which have been inputted so far, at least one of the plurality of recommended words comprising the characters which have been inputted so far.

RELATED APPLICATION(S)

This application is a continuation application of a prior applicationSer. No. 11/759,714, filed on Jun. 7, 2007, which is a continuation inpart under 35 U.S.C. § 120 of a prior application Ser. No. 10/951,250,filed on Sep. 27, 2004 and issued under U.S. Pat. No. 7,969,421, whichclaimed the benefit of a Korean patent application filed on Oct. 29,2003 in the Korean Intellectual Property Office and assigned Ser. No.10-2003-0075739, the entire disclosure of which is hereby incorporatedby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an apparatus and method forinputting characters using a touch screen in a portable terminal, and inparticular, to an apparatus and method for inputting characters withouterrors.

2. Description of the Related Art

A portable terminal may be equipped with a touch screen and its majorexample is a PDA (Personal Digital Assistant).

In general, the major components of the PDA are a computer, that is, aCPU (Central Processing Unit), a memory, and an OS (Operating System),and a variety of software programs and peripheral devices based on theOS. The PDA functions to gather, store, form, and search information.Recently, the PDA has been developed as a multi-functional deviceequipped with a portable phone module to enable voice calls and datacommunications (e.g., Web browsing).

One popular example of a PDA is the Palm Pilot produced by the PamComputing Company, and other similar personal, portable digital devicesare called PDA. Among products operating on Windows CE of Microsoft, adevice using a pen without a keyboard is called PPC (Palm-Sizes PC) anda device using a keyboard is called HPC (Handheld PC). The term “PDA”includes all these devices.

The PDA is usually provided with a touch screen. A user inputs acharacter using a soft keyboard displayed on the touch screen. The userinvokes an application program by touching an icon displayed on thetouch screen with his/her finger or a stylus pen. Characters may beinput by touching the soft keyboard displayed in a predetermined screenarea.

A pocket-size device such as the PDA, however, experiences frequentcharacter editing due to errors caused by the limited screen size. Thatis, the PDA has the shortcomings of inconvenience and unnecessary timeconsumption involved in frequent editing.

SUMMARY OF THE INVENTION

The present invention provides an apparatus and method for inputtingcharacters without errors using a touch screen in a portable terminal.

The present invention also provides an apparatus and method in which aninput character is displayed enlarged and the character is input to amain screen area upon detecting the release of touch when characters areinput using a touch screen in a portable terminal.

The present invention also provides an apparatus and method in which oneor more recommended words formed by combining input characters whichhave been input so far, and one of the recommended words is selected anddisplayed in a main screen area of a portable terminal equipped with atouch screen.

The present invention also provides an apparatus and method in which atouched character is displayed enlarged, and the character is input to amain screen area upon detecting a next touch in a portable terminalequipped with a touch screen.

The present invention also provides an apparatus and method in which anext input character is predicted and displayed enlarged in a portableterminal equipped with a touch screen.

The present invention also provides an apparatus and method in whichcharacters forming a word are sequentially touched by dragging, and theword is input to a main screen area upon detecting the release of touchin a portable terminal.

According to one aspect of the present invention, there is provided amethod of inputting characters in a portable terminal, comprising thesteps of: displaying a soft keyboard in a character input mode;recognizing a character touched on the soft keyboard; displaying therecognized character enlarged and displaying one or more recommendedwords formed by combining characters which have been touched so far in apredetermined screen area; and inputting the character displayedenlarged to a main screen area upon detecting the release of touch.

According to another aspect of the present invention, there is provideda method of inputting characters in a portable terminal, comprising thesteps of: displaying a soft keyboard in a character input mode;inputting a character, which has been touched on the soft keyboard, to amain screen area; predicting a next input character on the basis ofcharacters which have been touched so far; and displaying the predictedcharacter.

According to another aspect of the present invention, there is provideda method of inputting characters in a portable terminal, comprising thesteps of: displaying a soft keyboard in a character input mode;selecting one or more characters by dragging on the soft key board; andinputting the one or more characters to a main screen area upondetecting the release of touch.

According to another aspect of the present invention, there is providedan apparatus for inputting characters in a portable terminal,comprising: a touch screen, having a soft keyboard displayed thereon,for generating a touch signal upon detecting a touch on the softkeyboard in a character input mode; and a controller for recognizing,when a key button of the soft keyboard is touched, a charactercorresponding to the touched key button, displaying the characterenlarged, displaying one or more recommended words formed by combiningcharacters which have been touched so far in a predetermined screenarea, and inputting the character displayed enlarged to a main screenarea upon detecting the release of touch.

According to another aspect of the present invention, there is providedan apparatus for inputting characters in a portable terminal,comprising: a touch screen, having a soft keyboard displayed thereon,for generating a touch signal upon detecting a touch on the softkeyboard in a character input mode; and a controller for inputting, whena key button of the soft keyboard is touched, a character correspondingto the touched key button to a main screen area, predicting a next inputcharacter on the basis of characters which have been touched so far, anddisplaying the predicted character.

According to another aspect of the present invention, there is providedan apparatus for inputting characters in a portable terminal,comprising: a touch screen, having a soft keyboard displayed thereon,for generating a touch signal upon detecting a touch on the softkeyboard in a character input mode; and a controller for selecting oneor more characters by dragging on the soft keyboard and inputting theselected one or more characters to a main screen area detecting therelease of touch.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription when taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a block diagram of a portable terminal according to anexemplary embodiment of the present invention;

FIG. 2 is a flowchart illustrating an operation for inputting charactersin a portable terminal according to an exemplary embodiment of thepresent invention;

FIG. 3 is a flowchart illustrating an operation for inputting charactersin a portable terminal according to another exemplary embodiment of thepresent invention;

FIG. 4 is a flowchart illustrating an operation for inputting charactersin a portable terminal according to another exemplary embodiment of thepresent invention;

FIG. 5 is a flowchart illustrating an operation for canceling input ofcharacters in a portable terminal according to an exemplary embodimentof the present invention;

FIG. 6 is a flowchart illustrating an operation for detecting therelease of touch in a portable terminal according to an exemplaryembodiment of the present invention;

FIGS. 7A, 7B, and 7C illustrate examples of a touch screen when theoperation of FIG. 2 is performed according to an exemplary embodiment ofthe present invention;

FIGS. 8A, 8B, and 8C illustrate examples of a touch screen when theoperation of FIG. 3 is performed according to an exemplary embodiment ofthe present invention;

FIGS. 9A, 9B, 9C, and 9D illustrate examples of a touch screen when theoperation of FIG. 4 is performed according to an exemplary embodiment ofthe present invention; and

FIGS. 10A, 10B, and 10C illustrate examples of a touch screen when theoperation of FIG. 5 is performed according to an exemplary embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of the present invention will be described hereinbelow with reference to the accompanying drawings. In the followingdescription, well-known functions or constructions are not described indetail since they would obscure the invention in unnecessary detail.

The present invention relates to a technique for inputting characterswithout errors using a touch screen in a portable terminal. Thisinvention relates specifically to a method for inputting charactersusing a touch screen, wherein when the characters are input by touchinga soft keyboard displayed on the touch screen, a touched character isdisplayed in a predetermined screen area, and when the release of touchis detected, the character displayed on the predetermined screen area isinput to a main screen area. Herein, the predetermined screen area maybe either an area included in the main screen area or an area near a keybutton touched by a user. The release of touch may be detected when auser's finger (or stylus pen) is released from the touch screen, or whena next-touch is detected, or when the touch is maintained over apredetermined length of time.

FIG. 1 is a block diagram of a portable terminal according to thepresent invention. “Portable terminal” as used herein refers to anypocket-sized portable terminal providing a PC (Personal Computer)function and a cell phone function.

Referring to FIG. 1, an MPU (Micro-Processor Unit) 100 provides overallcontrol to the portable terminal. Specifically, the MPU 100 controlsdata processing and communication. According to the present invention,in addition to its typical functions, the MPU 100 controls error-freecharacter input when characters are input by touching a keyboarddisplayed on a touch screen 102. The typical process and control of theMPU 100 are not described herein.

A memory 101 includes a program memory, a data memory, and anon-volatile memory. The program memory stores programs for controllingthe entire operation of the portable terminal. It can be a flash memory.The data memory temporarily stores data generated during the operationof the portable terminal. A RAM (Random Access Memory) can be used asthe data memory. The non-volatile memory stores phone numbers registeredfor short dialing and system parameters. The non-volatile memory may bean EEPROM (Electrically Erasable Programmable Read Only Memory).

The touch screen 102 includes an LCD (Liquid Crystal Display) 103 and atouch panel 104 mounted on the LCD 103. The touch screen 102 displaysstate information generated during the operation of the portableterminal, and can also display moving pictures and still images. Thetouch screen 102 outputs to a touch signal receiver 105 an electricalanalog signal corresponding to a touch position. The touch signalreceiver 105 analyses the electrical analog signal received from thetouch screen 102 and outputs position data corresponding to the touchposition to the MPU 100.

A keypad 106 has a plurality of alphanumeric keys and function buttons.The keypad 106 outputs button input data corresponding to a pressedbutton to the MPU 100.

A radio communication module 107 is a module for communicating with a BS(Base Station) according to a predetermined communication standard. Itcan include an RF (Radio Frequency) module and a BBA (BaseBand Analog).

A CODEC (Coder-Decoder) 108 connected to the MPU 100, and a speaker 110and a microphone 109 connected to the CODEC 108 collectively form avoice input/output block for use in a phone call and voice recording.The CODEC 108 converts PCM (Pulse Code Modulation) data received fromthe MPU 100 to an analog voice signal and outputs it through the speaker110. The CODEC 108 also converts a voice signal received through themicrophone 109 to PCM data and provides the PCM data to the MPU 100.

FIG. 2 is a flowchart illustrating an operation for inputting charactersin a portable terminal according to an embodiment of the presentinvention.

Referring to FIG. 2, when a character input mode is set, a soft keyboard(e.g., QWERTY keyboard) is displayed on a touch screen in step 201. Thecharacter input mode has to be set in order to input characters whenusing services such as SMS (Short Message Service), e-mail, Webbrowsing, messenger, and so on.

With the soft keyboard displayed, it is checked whether a key button istouched in step 203. Upon detecting the touch of the key button, acharacter corresponding to the touched key button is displayed enlargedin step 205. The character may be displayed enlarged near the touchedkey button as shown in diagram (a) of FIG. 7, or may be displayedenlarged in a predetermined portion of a main screen area.Alternatively, the touched key button may be displayed with a specificcolor, so as to be easily noticed by the user. Further, the touch of thekey button can be recognized by the user by using a specific effect suchas a vibration effect or a sound effect. The character may be enlargedor displayed with a specific effect (e.g., color, vibration, sound,etc.) according to a user's preference.

In step 211, a word is predicted by combining characters which have beentouched so far, and the predicted word is displayed in a predeterminedportion of the main screen area as a recommended word. The charactersmay be combined using a well-known a T9 text input prediction andsuggestion scheme. Referring to diagram (a) of FIG. 7, for example, whenthe user inputs characters “frie”, a word “friend” is predicted anddisplayed in a predetermined portion of the main screen area. In thiscase, a plurality of recommended words may be displayed.

In step 207, it is checked whether the touch is released. As will bedescribed with reference to FIG. 6, the release of touch is detectedwhen a user's finger (or stylus pen) is released from the touch screen(step 601), or when a next touch is detected (step 603), or when thetouch is maintained over a predetermined length of time (step 605).

Referring back to FIG. 2, upon detecting the release of touch, thecharacter displayed enlarged is input to the main screen area in step209. The character may be input to the main screen area with a specificgraphic effect. For example, the character may be displayed as if it isdrawn into or flown over the main screen area as shown in diagram (b) ofFIG. 7. For another example, the character displayed near itscorresponding key button may be displayed as if it is disappearing intothe key button. Vibration or a specific sound may be produced tofacilitate user recognition.

If the release of touch is not detected, it is checked whether therecommended word is selected in step 213. The recommended word isselected by pressing a predetermined key button. When a plurality ofrecommended words is provided, the recommended word can be selected byrepeatedly pressing the predetermined key button until a desired word isselected.

If the recommended word is not selected, the procedure returns to step203. Otherwise, in step 215, the selected recommended word is input tothe main screen area, and the procedure returns to step 203. As shown indiagrams (a) and (b) of FIG. 7, a recommended word “friend” is displayedin a predetermined portion of the main screen area when the characters“frie” are input. As shown in diagram (c) of FIG. 7, when apredetermined key button (e.g., key button “●”) is touched, therecommended word is input to the main screen area. In this case,vibration, sound, or graphic effect may be provided to facilitate userrecognition.

Although not described in FIG. 2, a symbol mapped to its correspondingkey button may be displayed enlarged when the user touches a key button(e.g., input mode shift key, caps lock key, etc.) to which no characteris mapped. In this case, upon detecting the release of touch, theenlarged view of the symbol disappears and its corresponding function isperformed.

FIG. 3 is a flowchart illustrating an operation for inputting charactersin a portable terminal according to another embodiment of the presentinvention.

Referring to FIG. 3, when a character input mode is set, a soft keyboard(e.g., QWERTY keyboard) is displayed on a touch screen in step 301. Thecharacter input mode has to be set so as to input characters when usingservices such as SMS, e-mail, Web browsing, messenger, and so on.

With the soft keyboard displayed, it is checked whether a key button istouched in step 303. Upon detecting the touch of the key button, acharacter corresponding to the touched key button is displayed enlargedin step 305. The character may be displayed enlarged near the touchedkey button, or may be displayed enlarged in a predetermined portion of amain screen area. Alternatively, the touched key button may be displayedwith a specific color, so as to be easily noticed by the user. Further,the touch of the key button can be recognized by the user by using aspecific effect such as a vibration effect or a sound effect. Thecharacter may be enlarged or displayed with a specific effect (e.g.,color, vibration, sound, etc.) according to a user's preference.

In step 307, it is checked whether the touch is released. The release oftouch is detected when a user's finger (or stylus pen) is released fromthe screen, or when a next touch is detected, or when the touch ismaintained over a predetermined length of time.

Upon detecting the release of touch, in step 309, the characterdisplayed enlarged is input to the main screen area. In this case,vibration, sound, or graphic effect may be provided to facilitate userrecognition.

In step 311, it is determined whether a mode change request is receivedto change the current mode to a recommended mode. The recommended modeis defined as a mode in which a next input character can be predicted onthe basis of characters which have been input so far. The mode changingmay be automatically performed when the number of input characters isenough to form a word or may be performed according to a user'sselection.

If there is no mode change request, the procedure returns to step 303 soas to continue to detect the touch of key buttons. Otherwise, in step313, the current mode changes to the recommended mode.

In step 315, it is checked whether there is a key button touch. Upondetecting the key button touch, a character corresponding to the touchedkey button is input to the main screen area. The character may be inputto the main screen area immediately after a touch (or release of touch)is detected.

In step 319, the characters which have been input so far are combined topredict a next input character. In step 321, the predicted character isdisplayed enlarged, and the procedure returns to step 315. The predictedcharacter may be displayed enlarged near its corresponding key button ormay be displayed enlarged in a predetermined portion of the main screenarea. For example, as shown in FIG. 8, when the user intends to input“friend”, “n” is displayed enlarged immediately after a key button “e”is touched, and “d” is displayed enlarged immediately after a key button“n” is touched.

FIG. 4 is a flowchart illustrating an operation for inputting charactersin a portable terminal according to still another embodiment of thepresent invention.

Referring to FIG. 4, when a character input mode is set, a soft keyboard(e.g., QWERTY keyboard) is displayed on a touch screen in step 401. Thecharacter input mode has to be set so as to input characters when usingservices such as SMS, e-mail, Web browsing, messenger, and so on.

With the soft keyboard displayed, it is checked whether a key button istouched in step 403. Upon detecting the touch of the key button, acharacter corresponding to the touched key button is displayed enlargedin step 405. The character may be displayed enlarged near the touchedkey button, or may be displayed enlarged in a predetermined portion of amain screen area. Alternatively, the touched key button may be displayedwith a specific color, so as to be easily noticed by the user. Further,the touch of the key button can be recognized by the user by using aspecific effect such as a vibration effect or a sound effect. Thecharacter may be enlarged or displayed with a specific effect (e.g.,color, vibration, sound, etc.) according to a user's preference.

In step 407, it is checked whether a touch point is moved. The touchpoint is moved when the user moves his/her finger without releasing thetouch (hereinafter, referred to as “dragging”). If no dragging isdetected, it is checked whether the touch is released in step 413.Otherwise, it is checked whether a character is selected in step 409.The selection of the character may be detected when the user's fingerstays at a key button mapped to the character for a predetermined lengthof time or when the key button is slightly pressed.

If the selection of the character is not detected, it is checked whetherthe touch is released in step 413. Otherwise, the selected character isdisplayed enlarged in step 411. For example, as shown in diagram (a) ofFIG. 9, when the user first touches the key button “f”, the character“f” is displayed enlarged. In this state, when the user's finger isdragged to select the key button “r”, the character “r” is displayedenlarged. The process of selecting characters may be displayed tofacilitate user recognition by using a graphic effect (e.g., dottedarrow shown in FIG. 9). Alternatively, vibration or specific sound maybe generated upon selecting a character.

In the process of selecting characters by dragging, it is checkedwhether the touch is released in step 413. The release of touch may bedetected when a key button is released so as to input characters, whichhave been selected so far by dragging, to the main screen area. Also,the release of touch may be detected when a predetermined key button isreleased so as to input a word, which is formed by combining inputcharacters, to the main screen area.

If the release of touch is not detected, the procedure returns to step407 for detecting dragging. Upon detecting the release of touch, in step415, the characters selected by dragging is input to the main screenarea, and the procedure returns to step 403. In the case where acharacter combination function is provided, a complete word may bedisplayed in the main screen area even if the touch is released beforecharacter input is not finished.

FIG. 5 is a flowchart illustrating an operation for deleting an input ofcharacters in a portable terminal according to the present invention.

Referring to FIG. 5, when a character input mode is set, characters areinput by touching key buttons in step 501. While inputting thecharacters, in step 503, it is checked whether a cancel key button fordeleting an input of characters is touched. The cancel key button may bea backspace key or a delete key.

Upon detecting the touch of the cancel key button, in step 505, acharacter-to-be-deleted is displayed enlarged. Thecharacter-to-be-deleted may be a last input character or a characterlocated near a cursor. The character-to-be-deleted may be displayedenlarged near its corresponding key button or may be displayed in themain screen area. For example, as shown in diagram (a) of FIG. 10, whenthe backspace key button is touched, the last input character “s” isdisplayed enlarged as shown in diagram (b) of FIG. 10.

In step 507, it is checked whether the backspace key button is released.Upon detecting the release of the backspace key button, in step 509, thecharacter “s” displayed enlarged is deleted, and then the procedure isended. Consequently, as shown in diagram (c) of FIG. 10, the enlargedcharacter “s” is deleted.

If the release of the backspace key button is not detected, in step 511,it is checked whether the user's finger (or stylus pen) is dragged andreleased at a predetermined position (or key button). If no dragging isdetected, the procedure returns to step 507. Otherwise, in step 513, theenlarged character is re-displayed with a normal size, and then theprocedure is ended. That is, when the user does not intent to delete thecharacter, the user may drag his/her finger to the predeterminedposition and then releases it from that position.

As described above, the release of touch may be detected in a variousmanners when the character input mode is set.

FIG. 6 is a flowchart further illustrating the step 209 of FIG. 2 andthe step 307 of FIG. 3.

Referring to FIG. 6, it is checked whether a user's finger is releasedfrom a touch screen. If the finger is released from the touch screen, acurrent touch is released in step 607. Otherwise, in step 603, it ischecked whether there is a next touch (or another touch). Upon detectingthe next touch, in step 607, the next touch is released. If the nexttouch is not detected, in step 605, it is checked whether the touch ismaintained over a predetermined length of time. If the touch ismaintained over the predetermined length of time, the touch is releasedin step 607.

FIG. 7 illustrates examples of a touch screen when the operation of FIG.2 is performed.

Diagram (a) of FIG. 7 illustrates a touch screen where a key button “n”is touched in a state that characters “frie” have already been inputwhen a user intends to input “friend”. As a result, a character “n” isdisplayed enlarged near the key button “n”, and a recommended word“friend” is predicted on the basis of the characters “frie” which havebeen touched so far. The recommended word is displayed in apredetermined portion of a main screen area. In this state, when theuser releases the touch of the key button “n” and then touches a keybutton “d”, as shown in diagram (b) of FIG. 7, the character “n” isinput to the main screen area, and the touched character “d” isdisplayed enlarged near the key button “d”. Still, the recommended word“friend” is displayed in the predetermined portion of the main screenarea. In this state, if the user touches a predetermined key button(e.g., key button “●”), the recommended word is input to the main screenarea as shown in diagram (c) of FIG. 7.

FIG. 8 illustrates examples of a touch screen when the operation of FIG.3 is performed.

Diagram (a) of FIG. 8 illustrates a touch screen where a key button “e”is touched when a user intends to input “friend”. In this case, a nextinput character “n” is predicted on the basis of characters “frie” whichhave been input so far, and the predicted character “n” is displayedenlarged near its corresponding key button “n”. When the user touchesthe key button “n”, as shown in diagram (b) of FIG. 8, the character “n”is input to the main screen area. Then, a character “d” is predicted anddisplayed near its corresponding key button “d”.

FIG. 9 illustrates examples of a touch screen when the operation of FIG.4 is performed.

Diagram (a) of FIG. 9 illustrates a touch screen where a key button “f”is touched when a user intends to input “friend”. Then, a character “f”is displayed enlarged near the key button “f”. In this state, when theuser selects a key button “r” by dragging, as shown in diagram (b) ofFIG. 9, a character “r” is displayed enlarged near the key button “r”.Subsequently, when the user selects a key button “i” by dragging, acharacter “i” is displayed enlarged near the key button “i”. Characters“fri” which have been selected so far are displayed in a predeterminedportion of the main screen area. When characters forming a desired wordare all selected by dragging, the user releases the touch so as to inputthe word to the main screen area.

FIG. 10 illustrates examples of a touch screen when the operation ofFIG. 5 is performed.

When a backspace key button is touched in a state that “fries” are inputas shown in diagram (a) of FIG. 10, a last input character “s” isdisplayed enlarged as shown in diagram (b) of FIG. 10. The character “s”is deleted from the main screen area as shown in diagram (c) of FIG. 10when the user releases the touch of the backspace key button.

In accordance with the present invention as described above, when acharacter is input using a soft keyboard displayed in a touch screen, atouched character is displayed enlarged in a predetermined screen areaand input in a main screen area upon detecting the release of touch.Therefore, a user can confirm the touched character before it is input.In addition, the touched character can be input with user's approval(release of touch), thereby remarkably reducing input errors.

While the invention has been shown and described with reference to acertain preferred embodiment thereof, it is a mere exemplaryapplication. Thus, it will be understood by those skilled in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope of the invention as defined by theappended claims.

What is claimed is:
 1. A method of inputting characters in a portableterminal, comprising the steps of: displaying a plurality of characterson a keyboard; detecting a touch on the keyboard; displaying a firstcharacter corresponding to a key corresponding to the touch on thekeyboard as enlarged relative to other characters upon detecting thetouch; displaying a second character corresponding to a keycorresponding to a touch-move on the keyboard as enlarged relative toother characters on the keyboard upon detecting the touch-move without arelease of the touch; displaying the second character, which isdisplayed enlarged when detecting the release of the touch, in acharacter input area upon detecting the release of the touch on thekeyboard; and in response to displaying the second character, displayinga plurality of recommended words in a vicinity of the keyboard in thecharacter input area, wherein the recommended words are determined basedon the second character and other characters which have been displayedin the character input area.
 2. The method of claim 1, wherein thekeyboard is a QWERTY keyboard.
 3. The method of claim 1, wherein therelease of the touch is detected when an object is released from thekeyboard, or when a next touch is detected, or when the touch ismaintained over a predetermined length of time.
 4. The method of claim1, wherein the second character is displayed as enlarged near itscorresponding key or in a predetermined portion of the character inputarea.
 5. The method of claim 1, further comprising: selecting one of therecommended words; and displaying the selected recommended word in thecharacter input area.
 6. The method of claim 1, further comprising, whenthe character is displayed in the character input area, generating atleast one of a vibration, sound, and a graphic effect.
 7. The method ofclaim 1, wherein the portable terminal is a pocket-sized communicationterminal.
 8. A computer-readable medium comprising instructions that,when executed by at least one processor of a portable terminal, causethe portable terminal to execute the method of claim
 1. 9. The method ofclaim 1, further comprising, upon detecting a touch input on thedisplayed recommended word, displaying, in the character input area, therecommended word in lieu of the other characters and the secondcharacter which have been displayed.
 10. The method of claim 1, furthercomprising displaying a predicted character of the keyboard as enlarged,wherein the predicted character is determined as a character which hasnot been displayed among characters of the recommended word.